The latest opinion poll gives the 58-year-old incumbent a 10-point advantage over Capriles, but the 40-year-old challenger has cut the lead by half in just four months.

Chavez was favoured by 49.4 per cent of voters, compared to 39 per cent for Capriles in a poll released this week by Datanalisis. A significant number of voters, 11.6 per cent, remain undecided.

Other polls gave Chavez a bigger lead, while some found a statistical tie.

“All the big polling firms show a narrowing gap and a significant increase in voter intentions in favour of the opposition leader,” said Datanalisis president Luis Vicente Leon.

But Chavez, who declared victory over cancer in July, has voiced confidence that he would win re-election and use the next term to make his socialist revolution permanent.

“They know they are losing, that the gap is irreversible,” the president told thousands of supporters at a recent rally in the western state of Falcon, where people danced to the election song “Chavez, Heart of the People.”

True to his provocative style, Chavez has derided his rival as a “loser” and a “political illiterate” who would bring chaos to Venezuela.

Chavez said he believed he had beaten cancer and would be strong enough to rule for another six years if he scores another term.

“I think so, I feel great,” he told reporters when asked if he had fully recovered from his illness.

“If I didn’t feel strong enough, I wouldn’t be here. We’re even going to work at a faster pace.”

With Chavez dominating the public airwaves, Capriles has taken a page out of the president’s own playbook by bringing his campaign directly to the people, going door to door to meet with ordinary Venezuelans.

Capriles, who campaigns with a baseball cap in Venezuela’s colours, has sought to bring a fresh face to the opposition, which has been associated with an old system of parties that shared power for 40 years until Chavez’s rise.

“We must defeat Goliath, and each one of you is David. I am David, but each one of you is David too,” he told a recent rally that played his own campaign song “There is a Way”.

Capriles has seized on the country’s high murder rate – 50 homicides per 100,000 inhabitants last year – to criticise the president’s handling of the country’s crime wave.

“What I really miss is how it used to be when you could go out of your house without anything bad happening,” said Antonio Barrios, a woodworker of 54.

“It’s going to be 14 years we have had the same president, and violence and crime are worse... Now it’s somebody else’s turn.”